In the training of animals, particularly dogs, trainers employ various techniques for encouraging or discouraging various responses or behaviors of the animal. Typically, encouragement is effected by means of a small tidbit of food as a reward for desired behavior or responses. For undesired behavior or responses, a loud disapproving voice or a mild physical reprimand often is employed.
Various devices have been designed for applying a stimulus for undesirable behavior in the form of an electrical stimulus to the neck of the dog undergoing training. Many of these devices include radio signal receiver packs for responding to transmitted signals to administer the electrical stimulation, as desired, under control of the trainer operating the transmitter.
Five patents directed to specific features of remote radio controlled devices are the U.S. patents to Gonda U.S. Pat. No. 4,794,402; Gonda U.S. Pat. No. 4,802,482; Gonda U.S. Pat. No. 5,099,797; Farkas U.S. Pat. No. 5,054,428; and Gonda U.S. Pat. No. 5,193,484. In all of these devices, the dog collar is provided with an attached receiver/stimulus unit, which has a pair of electrodes projecting from it to contact the skin of the dog on the inner side of the collar. Whenever a behavior pattern requiring correction or cessation is exhibited by the dog, a signal is sent by the transmitter, under control of the trainer, to the receiver unit being worn on the collar of the dog. This signal operates circuitry within the receiving unit to cause the application of a mild electrical stimulus across the electrodes. This serves to provide the trainer with control over the actions of the dog over a relatively wide distance.
Other patents employing circuits similar to those disclosed in the above mentioned patents are designed to respond to the sound of a barking dog to operate circuitry for applying electrical stimulus to probes extending through a collar or attached to a dog collar. Three such U.S. patents are the patents to Gonda U.S. Pat. No. 4,202,293; Farkas U.S. Pat. No. 4,947,795 and So U.S. Pat. No. 5,601,054. Although the circuits described in these patents differ from one another, all of them are operated by sensors for detecting either the sound of or vibration of the barking dog to operate a switch, which in turn causes the circuitry within the devices to apply a short high voltage stimulus across a pair of electrodes in contact with the neck of the dog. The device of the Farkas patent operates to produce an initial, relatively low stimulus electrical pulse stimulation in response to the onset of barking. If the dog continues to bark, or barks again within a pre-established time frame, an increased level of electrical stimulation pulses is applied; and this takes place for each barking episode in a step-by-step fashion until the dog stops barking for a predetermined period of time, after which the device resets to its initial condition of operation.
Other devices for use in animal control are disclosed in the United States patent to Johnston U.S. Pat. No. 2,628,592 for an electrical calf weaner and the U.S. patent to Walker U.S. Pat. No. 4,945,860. The device of the Johnston patent is attached to the nose of a calf and is designed to be operated by a pressure activated switch when the calf attempts to press against the udder of a cow. Closure of the switch causes a mild electrical shock to be applied to the nose of the calf to facilitate the weaning process.
The Walker patent discloses a device similar to that of the Johnston patent; except that the pressure switch is placed on the forehead of the animal; so that if the animal pushes against an object, the switch is closed. Closure of the switch activates an electrical stimulation generating circuit to apply a mild stimulus to the head of the animal to deter it from the pushing behavior.
Situations exist when remote control devices, such as the dog training devices described above and the self-contained pressure-activated devices of the Johnston and Walker patents are not desired or required. One type of a situation where the devices described above are inconvenient to use or are not practical is in the training of an animal, such as a dog, to respond properly to a leash attached to its collar. As is well known, an untrained dog tends to pull hard against the leash which is being held by a trainer or its owner, resulting in unnecessary strain on behalf of both the person holding the leash and the dog. For proper behavior on a leash, a dog typically is taught to walk alongside of or slightly behind the owner, with a relatively slack leash, exerting no pull or very little pull by the dog against the leash.
Patents which are directed to electrical devices to assist in training a dog not to pull against a leash include the U.S. patent to Carter U.S. Pat. No. 2,023,930. The device of the Carter patent is designed with spaced apart electrodes which are attached to the dog collar. The electrodes are connected by wires extending along the length of a leash to a battery pack and switch, which is held by the trainer. When the trainer determines that the dog is exerting a pull on the leash or some other behavior which is not desired, the on/off switch in the battery pack is operated to send a signal to the electrodes on the collar. The signal is selected to give the dog a stimulus sufficient to cause the dog to obey a word or command or to take some desired action upon hearing a particular warning sound.
The patent to Green U.S. Pat. No. 5,494,002 is directed to an animal training device coupled to a leash. A trigger extends from the body of the device to contact the leash; and when a force is exerted by the leash which is in excess of a pre-established threshold, the tensioning of the leash activates a sound generator. The sound is one which is selected to startle the animal; so that it eventually learns to avoid the sound and to walk safely at the owner's side.
A different leash activated device is disclosed in the patent to Coulbourn U.S. Pat. No. 3,874,339. The device of this patent includes a stimulation circuit carried in a housing on the back side of the collar to which the leash is attached. Wires then extend from the shock circuit to a pair of electrodes located on the underside or lower neck side of the collar. When the dog exerts a pull in excess of a threshold amount, a switch is closed to apply a current across the electrodes and thereby to the neck of the dog or other animal. The amount of stimulus which is applied by the device is the same in all cases, irrespective of the force of the pull, so long as the minimum threshold is exceeded.
It is desirable to provide an improved animal training device, specifically a pressure-responsive training device which is simple and direct in operation, and which applies different levels of electrical stimulus to the animal which are directly proportional to the degree of departure from a desired behavior.